1. Field of the Invention
The present invention relates generally to a wireless location determination system and method, and, more particularly, to a wireless location determination system and method, which can improve the precision and reliability of location determination of a target and can facilitate the performance observation and maintenance of a location determination system even if the hardware resources of the location determination system are not reinforced.
2. Description of the Related Art
Wireless location determination technology is a technology for measuring the location of a terminal in satellite navigation systems such as a Global Positioning System (GPS), or wireless communication systems such as Code Division Multiple Access (CDMA), Wireless Local Area Network (WLAN), Ultra Wideband (UWB) and Bluetooth systems. Alongside an increasing demand for location information, the fields of use of wireless location determination technology have recently been expanding.
In particular, recently, research into local area high-precision wireless location determination systems, which use Radio Frequency Identification (RFID), ultrasonic waves, infrared rays, or UWB, has been actively conducted. For example, there has been developed indoor location determination technology which enables the locations of users or objects to be detected even in a region which GPS satellite signals cannot reach, such as the inside of buildings. Further, research into technology for detecting the location of a terminal through the transmission/reception of radio signals between a sensor and the terminal has been widely conducted.
Generally, the motion trajectory of a terminal is divided into a section in which the terminal is moving at uniform velocity and a section in which the terminal is moving at predetermined acceleration. In these sections, when the same motion model as the terminal is set and the location of the model is measured by an indoor location determination system, mismatching occurs between the motion of the model and the motion of the terminal. As a result, a disparity appears between the location of the terminal estimated by the location determination system and the actual location of the terminal, thus greatly deteriorating the precision of location determination.
Further, in the case of technology for measuring the location of a terminal by transmitting or receiving radio signals between a sensor and the terminal, it is usually difficult to perform this measurement as it is performed under ideal conditions. Further, when signals are bypassed, reflected or refracted due to the clustering of obstacles, errors may be included to some degree due to various factors such as multi-propagation, synchronization errors and measurement errors, and, thus information about a measured location is incorrect.
Therefore, in order to improve the reliability and precision of location determination in such a wireless location determination system, there have been mainly proposed in the prior art the methods of enhancing hardware performance by, for example, increasing the bandwidth of pulse signals for location determination, reducing the jitter of the clock of a transmitter/receiver, or more minutely sampling received pulse signals. However, the enhancement of such hardware performance is not only inevitably accompanied by an increase in cost, but is also inappropriate for the utilization of existing systems that have been already manufactured.